View source for U.S. Route 3

{{short description|North-south U.S. highway from Massachusetts to New Hampshire}}
{{Redirect|US 3|the band|Us3}}
{{Use mdy dates|date=February 2023}}
{{Use American English|date=February 2023}}
{{Infobox road
| country = USA
| type = US
| route = 3
| map = {{maplink|frame=yes|plain=yes|frame-align=center|frame-width=290|frame-height=290|type=line|from=U.S. Route 3.map}}
| map_custom = yes
| map_notes = US&nbsp;3 highlighted in red and US&nbsp;3 Bus. highlighted in blue
| length_mi = 277.90
| length_ref = {{citation needed|date=February 2018}}
| established = 1926{{citation needed|date=February 2018}}
| direction_a = South
| terminus_a = {{Jct|state=MA|MA|2A|MA|3}} in [[Cambridge, Massachusetts|Cambridge, MA]]
| junction = {{plainlist|
*{{Jct|state=MA|MA|2|MA|16}} in [[Cambridge, Massachusetts|Cambridge, MA]]
*{{Jct|state=MA|I|95|MA|128|MA|3A}} in [[Burlington, Massachusetts|Burlington, MA]]
*{{Jct|state=MA|I|495|road|[[Lowell Connector]]}} in [[Chelmsford, Massachusetts|Chelmsford, MA]]
*{{Jct|state=NH|NH|101A|Turnpike|Everett}} in [[Nashua, New Hampshire|Nashua, NH]]
*{{Jct|state=NH|I|293|Turnpike|Everett|NH|101}} near [[Manchester, New Hampshire|Manchester, NH]]
*{{Jct|state=NH|US|202|US|4}} in [[Concord, New Hampshire|Concord, NH]]
*{{jct|state=NH|I|93}} in [[Franconia, New Hampshire|Franconia, NH]]
*{{jct|state=NH|US|302}} in [[Carroll, New Hampshire|Carroll, NH]]
*{{jct|state=NH|US|2}} in [[Lancaster, New Hampshire|Lancaster, NH]]
}}
| direction_b = North
| terminus_b = {{Jct|state=QC|Route|257}} near [[Chartierville, Quebec|Chartierville, QC]]
| counties = '''MA:''' [[Middlesex County, Massachusetts|Middlesex]]<br/>'''NH:''' [[Hillsborough County, New Hampshire|Hillsborough]], [[Merrimack County, New Hampshire|Merrimack]], [[Belknap County, New Hampshire|Belknap]], [[Grafton County, New Hampshire|Grafton]], [[Coös County, New Hampshire|Coös]]
| states = [[Massachusetts]], [[New Hampshire]]
| system1 = {{infobox road/browselinks/USA|state=MA}}
| system2 = {{infobox road/browselinks/USA|state=NH}}
| browse = {{Us browse|previous_type=US|previous_route=2|next_type=US|next_route=4|route=[[List of United States Numbered Highways|US]]}}{{ma browse|previous_type=Route|previous_route=2A|route=MA|next_type=Route|next_route=3}}{{nh browse|previous_type=US|previous_route=2|route=NH|next_type=NH|next_route=3A}}{{New England browse|previous_route=5|next_route=6A}}
}}

'''U.S. Route&nbsp;3''' ('''US&nbsp;3''') is a [[United States Numbered Highway]] running {{Convert|277.90|mi|km}} from [[Cambridge, Massachusetts]], through [[New Hampshire]], to the [[Canada–United States border]] near [[Third Connecticut Lake]], where it connects to [[Quebec Route 257]].

[[Massachusetts Route 3|Massachusetts&nbsp;Route&nbsp;3]] connects to the southern terminus of US&nbsp;3 in Cambridge and continues south to [[Cape Cod]]. Though it shares a number, it has never been part of US&nbsp;3. Both routes, which connect end-to-end, are treated as a single {{Convert|91.3|mi|km|adj = on}} state highway by the [[Massachusetts Department of Transportation]] (MassDOT). From Cambridge to [[Burlington, Massachusetts|Burlington]], US&nbsp;3 is routed on surface streets through the dense suburbs in the [[Greater Boston]] area. After a brief concurrency with [[Interstate 95 in Massachusetts|Interstate&nbsp;95]] (I-95) and [[Massachusetts Route 128|Route&nbsp;128]], the route follows its own freeway northwest, bypassing [[Lowell, Massachusetts|Lowell]] and entering New Hampshire at [[Nashua, New Hampshire|Nashua]], becoming the [[Everett Turnpike]].

In New Hampshire, current and former parts of US&nbsp;3 are known as the [[Daniel Webster Highway]]. From Burlington, Massachusetts, to Nashua, New Hampshire, US&nbsp;3 is a [[freeway]]. The segment in New Hampshire is a free portion of the Everett Turnpike, while the portion in Massachusetts is known as the '''Northwest Expressway'''. From where it leaves the Everett Turnpike in Nashua northward, US&nbsp;3 is generally a two-to-four lane at-grade road, though there are two [[Super two (road)|super-two]] freeway portions in northern New Hampshire, one on the [[Laconia, New Hampshire|Laconia]] Bypass, and one where US&nbsp;3 and [[Interstate 93 in New Hampshire|I-93]] use the [[Franconia Notch]] Parkway. The route serves as a major local arterial, connecting many of the cities of the densely populated [[Merrimack Valley]]. North of the [[White Mountains (New Hampshire)|White Mountains]], the route serves as one of the only north–south roads connecting the communities of the [[Great North Woods Region (New Hampshire)|Great North Woods Region]] and has New Hampshire's only border crossing between the US and Canada.

==Route description==
{{lengths table|length_ref=<ref name="NHDOT Roads" />}}
|-
|{{abbr|MA|Massachusetts}}
|{{convert|35.70|mi|km|disp=table}}<!--91.2217 - 55.5217 = 35.5158-->
|-
|{{abbr|NH|New Hampshire}}
|{{convert|241.953|mi|km|disp=table}}
|-
|Total
|{{convert|277.653|mi|km|disp=table}}
|}

===Massachusetts===

====Cambridge to Burlington====
US&nbsp;3 begins in the south along Memorial Drive in [[Cambridge, Massachusetts|Cambridge]], along the [[Charles River]], at an interchange with [[Massachusetts Avenue (metropolitan Boston)|Massachusetts Avenue]] ([[Massachusetts Route 2A|Route&nbsp;2A]]). The road continues as southbound Route&nbsp;3 toward [[Downtown Boston]], while northbound US&nbsp;3 heads west, then north along the river toward [[Harvard University]], joining with [[Massachusetts Route 2|Route&nbsp;2]] along the way. It runs along the north bank of the Charles River, opposite [[Soldiers Field Road]] in [[Allston]] along this stretch. Passing south of [[Harvard Square]], US&nbsp;3 and Route&nbsp;2 transition onto the [[Fresh Pond Parkway]] and join [[Massachusetts Route 16|Route&nbsp;16]]. Near [[Alewife station]], Route&nbsp;2 splits off as a [[freeway]] to the west (Concord Turnpike), while US&nbsp;3 and Route&nbsp;16 stay on the [[Alewife Brook Parkway]]. Shortly thereafter, US&nbsp;3 splits from the parkway (which continues as Route&nbsp;16) and joins Route&nbsp;2A (Massachusetts Avenue) westbound, crossing into [[Arlington, Massachusetts|Arlington]]. In the center of town, US&nbsp;3 and Route&nbsp;2A split from Massachusetts Avenue and overlap briefly with [[Massachusetts Route 60|Route&nbsp;60]] before continuing along Mystic Street. Route&nbsp;2A splits from US&nbsp;3 just to the north. US&nbsp;3 continues through parts of [[Winchester, Massachusetts|Winchester]] and [[Woburn, Massachusetts|Woburn]] without any major intersections before entering [[Burlington, Massachusetts|Burlington]] and interchanging with [[Interstate 95 in Massachusetts|I-95]] and [[Massachusetts Route 128|Route&nbsp;128]] (Yankee Division Highway) at exit&nbsp;51A. US&nbsp;3 joins the freeway to connect with the Northwest Expressway, while its historic surface alignment continues as [[Massachusetts Route 3A|Route&nbsp;3A]].

====Burlington to Tyngsborough (Northwest Expressway)====
{{Attached KML|from=Northwest Expressway (Massachusetts)}}
[[File:US Route 3 - Massachusetts - 4207347331.jpg|thumb|Signage on US Route 3, approaching the intersection with [[Interstate 495 (Massachusetts)|Interstate 495]] and [[Massachusetts Route 110]] in [[Chelmsford, Massachusetts|Chelmsford]]]]
US&nbsp;3 runs along {{Convert|1.6|mi|km}} of I-95 (Route&nbsp;128) in a [[wrong-way concurrency]] before exiting at exit&nbsp;50A onto its own freeway, the Northwest Expressway.

Originally built in the 1950s, before the cancelation of the [[Inner Belt (Boston)|Inner Belt]], the US&nbsp;3 freeway was to have extended into metro Boston before being truncated to I-95. Consequently, a partially completed [[cloverleaf interchange]] connects US&nbsp;3 to I-95. Exit numbers on the US&nbsp;3 freeway start at milemarker&nbsp;72 since Route&nbsp;3 and US&nbsp;3 are counted as one highway by MassDOT.

The freeway closely parallels Route&nbsp;3A, the historic alignment of US&nbsp;3, along its entire {{Convert|19|mi|km|adj = on}} length from Burlington to the [[New Hampshire]] state border. It passes through [[Billerica, Massachusetts|Billerica]] and into [[Chelmsford, Massachusetts|Chelmsford]], where it connects with [[Interstate 495 (Massachusetts)|I-495]] and the [[Lowell Connector]], a freeway spur into downtown [[Lowell, Massachusetts|Lowell]]. Continuing north, the freeway briefly enters Lowell, then passes through North Chelmsford and [[Tyngsborough, Massachusetts|Tyngsborough]] before crossing the [[Northern boundary of Massachusetts|state line]] into [[Nashua, New Hampshire]]. The freeway continues north as the [[Everett Turnpike]].

The Burlington to Tyngsborough area maintains a [[501(c)(6)]] [[Nonprofit organization|nonprofit]] representative entity known as the Middlesex 3 Coalition<ref>{{cite web |url=https://www.middlesex3.com/ |title=Middlesex 3 |author=<!--Not stated--> |date=January 1, 2022 |website=www.middlesex3.com |publisher=Middlesex 3 Coalition |access-date=February 20, 2022 |quote= |archive-url=https://web.archive.org/web/20230511195359/https://www.middlesex3.com/m3-tma-homepage/ |archive-date=11 May 2023}}</ref> and its affiliate agency the Middlesex 3 TMA,<ref>{{cite web |url=https://www.middlesex3tma.com/ |title=Middlesex 3 (TMA) |author=<!--Not stated--> |date=January 1, 2022 |website=middlesex3tma.com |publisher=Middlesex 3 Transportation Management Association (TMA) |access-date=February 20, 2022 |quote= |archive-url=https://web.archive.org/web/20160705001445/https://www.middlesex3tma.com/ |archive-date=5 July 2016}}</ref> which provides collaborative support to businesses and individuals within the jurisdiction to build consensus on transportation and developmental needs.

===New Hampshire===
US&nbsp;3 passes through most of the state's major cities and towns and is the only highway to extend from the [[Massachusetts]] state border in the south to the Canadian border in the north. Running for {{Convert|242|mi|km}} in New Hampshire, US&nbsp;3 is by far the longest signed highway in the state. For much of its routing, US&nbsp;3 closely parallels I-93, serving as a local route to the freeway.

==== Everett Turnpike (Nashua) ====
US&nbsp;3 crosses the state border into [[Nashua, New Hampshire|Nashua]] and immediately becomes concurrent with the [[Everett Turnpike]], running on the freeway for {{Convert|6.7|mi|km}} along the western side of the city. 

==== Daniel Webster Highway, local roads, and NH 28 concurrency (Nashua –&nbsp;Suncook) ====
US&nbsp;3 leaves the Everett Turnpike at exit&nbsp;7E, crosses [[New Hampshire Route 101A]] (NH&nbsp;101A) and turns northeast for approximately {{convert|1.5|mi|km}} along a segment known as the Henri Burque Highway, before turning north onto Concord Street, which soon becomes known as the [[Daniel Webster Highway]]. (Some locals erroneously refer to the Everett Turnpike from exit&nbsp;7 through the [[Interstate 293|I-293]] interchange as US&nbsp;3 and refer to the actual US&nbsp;3 only as the Daniel Webster Highway or "Old Route&nbsp;3".)

US&nbsp;3 continues north through the town of [[Merrimack, New Hampshire|Merrimack]] and into [[Bedford, New Hampshire|Bedford]], where it becomes South River Road. The highway parallels I-293 until it turns east in [[Manchester, New Hampshire|Manchester]] and then crosses the [[Merrimack River]] on Queen City Avenue, just after its intersection with I-293/[[New Hampshire Route 3A|NH&nbsp;3A]] and [[New Hampshire Route 114|NH&nbsp;114A]]. US&nbsp;3 and NH&nbsp;3A are signed in a wrong-way concurrency for approximately {{Convert|0.6|mi|km}} before US&nbsp;3 turns north onto Elm Street toward downtown Manchester. After approximately {{convert|2.2|mi|km}}, US&nbsp;3 turns east onto Webster Street, then joins [[New Hampshire Route 28|NH&nbsp;28]] to proceed in a northeasterly direction toward Hooksett, interchanging with [[Interstate 93 in New Hampshire|I-93]]. The two routes continue as Hooksett Road, then the Daniel Webster Highway.

==== In Concord ====
In [[Suncook, New Hampshire|Suncook]], NH&nbsp;28 leaves to the northeast, and US&nbsp;3 proceeds northwest toward [[Concord, New Hampshire|Concord]] on Pembroke Street, becoming Manchester Street when it enters the Concord city limits. After crossing the Merrimack River and interchanging with I-93, US&nbsp;3 intersects NH&nbsp;3A (South Main Street), which terminates at its parent route. US&nbsp;3 traverses downtown Concord as North and South Main streets (briefly overlapping with [[U.S. Route 202 in New Hampshire|US&nbsp;202]] and [[New Hampshire Route 9|NH&nbsp;9]]), then follows North State Street to Fisherville Road to Village Street in [[Penacook, New Hampshire|Penacook]] before crossing the [[Contoocook River]] into [[Boscawen, New Hampshire|Boscawen]]. 

==== Further north (Boscawen – Lincoln) ====
US&nbsp;3 travels north through Boscawen, briefly overlapping with [[U.S. Route 4 in New Hampshire|US&nbsp;4]]. The highway parallels the Merrimack River north into [[Franklin, New Hampshire|Franklin]], where the highway meets [[New Hampshire Route 11|NH&nbsp;11]]. US&nbsp;3 joins NH&nbsp;11 and turns east; NH&nbsp;3A also resumes at this intersection, continuing north. US&nbsp;3 and NH&nbsp;11 briefly form a three-route concurrency with [[New Hampshire Route 127|NH&nbsp;127]] in Franklin, then pass through [[Tilton, New Hampshire|Tilton]], crossing [[New Hampshire Route 132|NH&nbsp;132]] and passing the western end of [[New Hampshire Route 140|NH&nbsp;140]]. Continuing northeast past [[Lake Winnisquam]], US&nbsp;3 and NH&nbsp;11 reach [[Laconia, New Hampshire|Laconia]] and turn onto the Laconia–[[Gilford, New Hampshire|Gilford]] Bypass, intersecting with [[New Hampshire Route 106|NH&nbsp;106]], [[New Hampshire Route 107|NH&nbsp;107]], and [[New Hampshire Route 11A|NH&nbsp;11A]]. At the northern end of the bypass, US&nbsp;3 and NH&nbsp;11 split after a {{Convert|17.3|mi|km|adj = on}} overlap, with the U.S. Route continuing north on Lake Street to [[Weirs Beach, New Hampshire|Weirs Beach]] and an intersection with [[New Hampshire Route 11B|NH&nbsp;11B]]. US&nbsp;3 continues north as the [[Daniel Webster Highway]] to [[Meredith, New Hampshire|Meredith]] at the northern end of Meredith Bay on [[Lake Winnipesaukee]]. In Meredith, US&nbsp;3 intersects the northern terminus of NH&nbsp;106, then joins [[New Hampshire Route 25|NH&nbsp;25]] and continues north past [[Squam Lake]] into [[Holderness, New Hampshire|Holderness]], passing the western terminuses of [[New Hampshire Route 25B|NH&nbsp;25B]] and [[New Hampshire Route 113|NH&nbsp;113]]. Through Holderness, US&nbsp;3 and NH&nbsp;25 gradually turn west, then southwest, passing the southern end of [[New Hampshire Route 175|NH&nbsp;175]] and then reaching the northern end of [[New Hampshire Route 132|NH&nbsp;132]] in [[Ashland, New Hampshire|Ashland]].

[[Image:US3LincolnNH.jpg|thumb|US&nbsp;3 in [[Lincoln, New Hampshire]]]]

From Ashland to [[North Woodstock, New Hampshire|North Woodstock]], US&nbsp;3 proceeds north, roughly paralleling [[Interstate 93|I-93]] in the [[Pemigewasset River]] valley. Along this stretch it passes through the towns of [[Plymouth, New Hampshire|Plymouth]] (NH&nbsp;25 splits from US&nbsp;3 near I-93 in Plymouth, which also marks the true northern terminus of NH&nbsp;3A), [[Campton, New Hampshire|West Campton]] (where it meets the western end of [[New Hampshire Route 49|NH&nbsp;49]], the principal access road to [[Waterville Valley, New Hampshire|Waterville Valley]]), [[Thornton, New Hampshire|Thornton]], and [[Woodstock, New Hampshire|Woodstock]]. In [[North Woodstock, New Hampshire|North Woodstock]], US&nbsp;3 crosses [[New Hampshire Route 112|NH&nbsp;112]] (known to the east as the [[Kancamagus Highway]]).

==== Interstate 93 concurrency through the Franconia Notch State Park (Lincoln – Franconia) ====
Continuing north, US&nbsp;3 joins with I-93 as it passes through [[Franconia Notch State Park]], one of the more scenic drives in the [[White Mountains (New Hampshire)|White Mountains]]. This stretch of freeway is known as the Franconia Notch Parkway and is a rare section of [[Interstate Highway]] with only one lane in each direction.

==== Northernmost end (Franconia – Pittsburg) ====
US&nbsp;3 separates from I-93 at exit&nbsp;35, shortly north of the northern park boundary in [[Franconia, New Hampshire|Franconia]]. From there, [[New Hampshire Route 141|NH&nbsp;141]] branches northwest and US&nbsp;3 heads north and east toward [[Twin Mountain, New Hampshire|Twin Mountain]] and a junction with [[U.S. Route 302 in New Hampshire|US&nbsp;302]]. This portion of the road is noted for fairly frequent [[moose]] sightings, especially during sunrise and sunset when moose are particularly active.

Heading north from Twin Mountain, US&nbsp;3 passes through the village of [[Carroll, New Hampshire|Carroll]], where [[New Hampshire Route 115|NH&nbsp;115]] branches to the northeast and US&nbsp;3 bears to the northwest and the town of [[Whitefield, New Hampshire|Whitefield]]. In the center of Whitefield, [[New Hampshire Route 142|NH&nbsp;142]] branches to the northwest and [[New Hampshire Route 116|NH&nbsp;116]] crosses, running roughly southwest to northeast. US&nbsp;3 continues north to [[Lancaster, New Hampshire|Lancaster]], where it joins [[U.S. Route 2 in New Hampshire|US&nbsp;2]] in the town center, and where [[New Hampshire Route 135|NH&nbsp;135]] branches off to the west. After US&nbsp;2 leaves to the west, US&nbsp;3 continues north, roughly paralleling the course of the [[Connecticut River]] (which also forms the border with [[Vermont]]), through [[Northumberland, New Hampshire|Northumberland]] and [[Groveton, New Hampshire|Groveton]], where [[New Hampshire Route 110|NH&nbsp;110]] ends. North of Groveton, US&nbsp;3 continues to follow the river, through [[Stratford, New Hampshire|Stratford]], [[North Stratford, New Hampshire|North Stratford]], and [[Columbia, New Hampshire|Columbia]], until it reaches [[Colebrook, New Hampshire|Colebrook]], where it crosses [[New Hampshire Route 26|NH&nbsp;26]] and meets the southern terminus of [[New Hampshire Route 145|NH&nbsp;145]]. Still following the Connecticut River north, US&nbsp;3 passes through portions of [[Stewartstown, New Hampshire|Stewartstown]] and [[Clarksville, New Hampshire|Clarksville]]. In Stewartstown, the road turns more directly east (still following the Connecticut River, which is no longer a boundary), before resuming a northeasterly direction through [[Pittsburg, New Hampshire|Pittsburg]]. Its last major intersection is at the northern terminus of NH&nbsp;145. US&nbsp;3 continues north for another {{Convert|22|mi|km}}, eventually reaching the [[Pittsburg–Chartierville Border Crossing]], where the road crosses into [[Chartierville, Quebec]], and becomes [[Quebec Route 257]].

In total, US&nbsp;3 runs along the Connecticut River and its source lakes for approximately {{Convert|70|mi|km}}. Sections of US&nbsp;3 in Colebrook are named after Scott E. Phillips and Leslie G. Lord, members of the [[New Hampshire State Police]] killed in the line of duty on [[Carl Drega|August 19, 1997]].<ref>{{cite press release |url=https://www.nh.gov/safety/divisions/nhsp/newsevents/2019/20190515-colebrook-signs.htm |title=New Memorial Highway Signs, Colebrook, New Hampshire |website=NH.gov |publisher=[[New Hampshire Department of Safety]] |date=May 15, 2019 |accessdate=July 14, 2021}}</ref>

==History==

===New England route===
{{Main|Massachusetts Route 3#History}}
[[Image:New England 6.svg|75px|right]]
Before the establishment of the U.S. Numbered Highway System, the section of US&nbsp;3 and [[Massachusetts Route 3|Route&nbsp;3]] from [[Orleans, Massachusetts]], to [[Colebrook, New Hampshire]], was part of the [[New England road marking system]] as [[New England Route 6]]. It was replaced in its entirety with the establishment of US&nbsp;3 and Route&nbsp;3 in 1926.

===Massachusetts===
US&nbsp;3 in Massachusetts closely follows the route of the early 19th-century [[Middlesex Canal]] and [[Middlesex Turnpike (Massachusetts)|Middlesex Turnpike]].

The modern Northwest Expressway was begun near [[Massachusetts Route 110|Route&nbsp;110]] in [[Lowell, Massachusetts|Lowell]] before [[World War II]]. In the 1950s, it was extended south to Route&nbsp;128 (later overlapped by I-95), and, by the 1960s, it was completed north from [[Chelmsford, Massachusetts|Chelmsford]] to New Hampshire. By 2005, the chronically congested four-lane road, largely with antiquated ramps around Lowell, was widened to six lanes (as it had been in Nashua, New Hampshire, a few years prior) with a breakdown lane on both the left and right sides of the road, and many interchanges were modernized in what was comically known as "The Big Wide", in reference to Massachusetts' other "Big" construction project (the [[Big Dig]]). The roadbed and bridges were built to support a fourth lane in each travel direction for future expansion. The $365-million (equivalent to ${{Formatprice|{{inflation|US-GDP|365000000|2005}}}} in {{Inflation/year|index=US-GDP}}{{Inflation/fn|index=US-GDP}}), {{convert|21|mi|km|adj=on}} widening project was completed in 2005 from [[Burlington, Massachusetts|Burlington]] to the New Hampshire border.

The final section of the expressway was planned for inner suburban towns northwest of [[Boston]]. The expressway was to supply a new route for US&nbsp;3, between Route&nbsp;128 and the canceled [[Interstate 695 (Massachusetts)|I-695]] (Inner Belt). This was one of the expressway projects canceled in Governor [[Francis Sargent]]'s 1970 moratorium on expressway construction within Route&nbsp;128. The latter section of the expressway was a key component of the "Master Plan Highway Plan for Metropolitan Boston". The highway would have traveled through Lexington, Arlington, Medford, Somerville, and Cambridge, before linking with the Inner Belt Expressway.{{Cn|date=October 2022}}

The original plan called for US&nbsp;3 and [[Massachusetts Route 2|Route&nbsp;2]] to link up at the Lexington–Arlington border and continue southeasterly, crossing Route&nbsp;16/Mystic Valley Parkway at the Arlington–Somerville border and proceeding into Cambridge toward Union Square, Somerville. A 1962 plan called for Route&nbsp;2 and US&nbsp;3 to converge at [[Alewife Brook Parkway]] with a longer stretch of new highway for US&nbsp;3 paralleling Lowell Street in Lexington and Summer Street in Arlington.{{Cn|date=October 2022}}

Exit numbers along the Northwest Expressway section in Massachusetts were to be changed to mileage based numbers under a project to start in 2016,<ref>{{Citation |title=COMMBUYS Solicitation:FAP# HSIP-002S(874) Exit Signage Conversion to Milepost-Based Numbering System along Various Interstates, Routes and the Lowell Connector |publisher=Commonwealth of Massachusetts}}</ref> but that project was postponed.<ref>{{cite web |author=Robert H. Malme|year=2017|title=Massachusetts Interstate Highways Exit Lists|url=http://www.malmeroads.net/mass21c/intexits.html|access-date=January 18, 2017}}</ref> In November 2019, the MassDOT announced it would be proceeding with the project in 2020.<ref name="Renumbering">{{cite web|url=https://www.newmassexits.com/MassDOT_Documents/Project_Documents/Handout_1.pdf|title = Milepost-based Exit Renumbering|publisher=[[Massachusetts Department of Transportation]]|date=December 5, 2019|access-date=December 5, 2019}}</ref>

==Termini==
According to the [[American Association of State Highway and Transportation Officials]] (AASHTO) route log, the southern terminus of US&nbsp;3 is at the junction of [[Massachusetts Route 2A|Route&nbsp;2A]] and [[Massachusetts Route 3|Route&nbsp;3]] in [[Cambridge, Massachusetts|Cambridge]], which is where Route&nbsp;2A crosses the Charles along the [[Harvard Bridge]] (also known as the Massachusetts Avenue Bridge).<ref>{{cite web |publisher= AASHTO |year= 2009 |title= Route Number Database |url= http://route.transportation.org/Pages/U.S.RouteNumberDatabase%28Dec2009%29.aspx | access-date= October 14, 2015}}</ref> This is a change from AASHTO's 1989 Route Log which placed the terminus at [[U.S. Route 20 in Massachusetts|US&nbsp;20]] in Boston, where [[Massachusetts Route 2|Route&nbsp;2]] currently meets US&nbsp;20 after crossing the [[Charles River]] at the [[Boston University Bridge]].<ref>{{cite web |publisher= AASHTO |year= 1989 |title= U.S. Numbered Highways, 1989 Edition |url= http://route.transportation.org/Documents/USRN_page_001_to_054.pdf| access-date= October 14, 2015}}</ref> This was where US&nbsp;3 met US&nbsp;1 until that highway was rerouted in 1971.

The original northern terminus of US&nbsp;3 (in 1926) was at [[Colebrook, New Hampshire]], but the highway was extended to [[West Stewartstown, New Hampshire|West Stewartstown]] in 1928 and to [[Pittsburg, New Hampshire|Pittsburg]] in 1937. Colebrook was the northern terminus again from 1939 to 1940. Since 1940, the highway has run through Pittsburg to the [[Pittsburg–Chartierville Border Crossing]].

==Major intersections==
Although MassDOT inventories Route&nbsp;3 and US&nbsp;3 as one continuous route, this table includes the mileage only for US&nbsp;3 starting from its southern terminus in Cambridge.
{{jcttop|old|state_col=state|length_ref=<ref name="MassDOT Route Log">{{cite web|author=Planning Division|title=Massachusetts Highway Route Log|publisher=[[Massachusetts Department of Transportation]]|url=http://www.massdot.state.ma.us/planning/Main/MapsDataandReports/Maps/HighwayRouteLog.aspx|date=2012|access-date=February 2, 2017|archive-date=August 18, 2018|archive-url=https://web.archive.org/web/20180818000005/http://www.massdot.state.ma.us/planning/Main/MapsDataandReports/Maps/HighwayRouteLog.aspx|url-status=dead}}</ref><ref name="NHDOT Roads">{{cite web|url=http://www.granit.unh.edu/data/search?dset=roads_dot|title=NH Public Roads|author=Bureau of Planning & Community Assistance|date=February 20, 2015|publisher=[[New Hampshire Department of Transportation]]|place=Concord, New Hampshire|access-date=April 7, 2015}}</ref><ref name="NH Town Maps">{{Cite FTP |url=ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/|title=Nodal Reference 2015, State of New Hampshire|author=Bureau of Planning & Community Assistance|date=April 3, 2015|server=[[New Hampshire Department of Transportation]]|url-status=dead|access-date=April 7, 2015}}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/NASHUA_Wallmap.pdf City of Nashua, Hillsborough County]{{dead link|date=May 2025|bot=medic}}{{cbignore|bot=medic}}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/MERRIMACK_Wallmap.pdf Town of Merrimack, Hillsborough County]{{Dead link|date=August 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/BEDFORD_Wallmap.pdf Town of Bedford, Hillsborough County]{{Dead link|date=August 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/MANCHESTER_Wallmap.pdf City of Manchester, Hillsborough County]{{Dead link|date=August 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/HOOKSETT_Wallmap.pdf Town of Hooksett, Merrimack County]{{Dead link|date=August 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/ALLENSTOWN_Wallmap.pdf Town of Allenstown, Merrimack County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/PEMBROKE_Wallmap.pdf Town of Pembroke, Merrimack County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/CONCORD_Wallmap.pdf City of Concord, Merrimack County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/BOSCAWEN_Wallmap.pdf Town of Boscawen, Merrimack County]{{Dead link|date=August 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/FRANKLIN_Wallmap.pdf City of Franklin, Merrimack County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/TILTON_Wallmap.pdf Town of Tilton, Belknap County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/BELMONT_Wallmap.pdf Town of Belmont, Belknap County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/LACONIA_Wallmap.pdf City of Laconia, Belknap County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/GILFORD_Wallmap.pdf Town of Gilford, Belknap County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/MEREDITH_Wallmap.pdf Town of Meredith, Belknap County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/CENTER%20HARBOR_Wallmap.pdf Town of Center Harbor, Belknap County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/HOLDERNESS_Wallmap.pdf Town of Holderness, Grafton County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/ASHLAND_Wallmap.pdf Town of Ashland, Grafton County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/PLYMOUTH_Wallmap.pdf Town of Plymouth, Grafton County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/CAMPTON_Wallmap.pdf Town of Campton, Grafton County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/THORNTON_Wallmap.pdf Town of Thornton, Grafton County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/WOODSTOCK_Wallmap.pdf Town of Woodstock, Grafton County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/LINCOLN_Wallmap.pdf Town of Lincoln, Grafton County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/FRANCONIA_Wallmap.pdf Town of Franconia, Grafton County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/CARROLL_Wallmap.pdf Town of Carroll, Coos County]{{Dead link|date=August 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/WHITEFIELD_Wallmap.pdf Town of Whitefield, Coos County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/NORTHUMBERLAND_Wallmap.pdf Town of Northumberland, Coos County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/STRATFORD_Wallmap.pdf Town of Stratford, Coos County]{{Dead link|date=August 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/COLEBROOK_Wallmap.pdf Town of Colebrook, Coos County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}
*[ftp://dot%2Ecity:streetmap@nhftp.admin.state.nh.us/2015_FULL_SIZE_PDFS/PITTSBURG_Wallmap.pdf Town of Pittsburg, Coos County]{{Dead link|date=July 2025 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>|location_ref=<ref name="NHDOT Roads" /><ref name="NH Town Maps" />|exit_ref=<ref name="US 3 Renumbering">{{cite web|url=https://www.newmassexits.com/MassDOT_Documents/Project_Documents/US_3.pdf|title=US 3 Exit Renumbering|publisher=[[Massachusetts Department of Transportation]]|date=December 5, 2019|access-date=December 24, 2019|archive-url=https://web.archive.org/web/20201023054833/https://newmassexits.com/images/MassDOT_Documents/Project_Documents/US_3.pdf|archive-date=October 23, 2020|url-status=dead}}</ref>}}
{{MAint|old
|sspan=24
|county=Middlesex
|cspan=24
|location=Cambridge
|lspan=6
|mile=0.000<!-- calculated from Massachusetts Route 3 milepoint 56.085 at Massachusetts Avenue -->
|mspan=2
|road={{jct|state=MA|MA|3|dir1=south|name1=[[Memorial Drive (Cambridge)|Memorial Drive]]|city1=Boston}}
|notes=Continuation south
}}
{{MAint|old
|mile=none
|type=incomplete
|road={{jct|state=MA|MA|2A|city1=Cambridge|city2=Roxbury|name1=[[Massachusetts Avenue (Boston)|Massachusetts Avenue]]&nbsp;/ [[Harvard Bridge]]}}
|notes=Diamond interchange; no southbound access to Route 2A west
}}
{{MAint|old
|espan=7
|ospan=7
|type=concur
|mile=1.047
|road={{jct|state=MA|MA|2|dir1=east|name1=[[Boston University Bridge]]|city1=Cambridgeport|city2=Brookline}}
|notes=[[Roundabout interchange]]; south end of concurrency with Route&nbsp;2
}}
{{MAint
|type=concur
|mile=3.975
|road={{jct|state=MA|MA|16|dir1=west|name1=Huron Avenue|city1=Watertown|city2=West Newton}}
|notes=South end of concurrency with Route&nbsp;16
}}
{{MAint
|type=concur
|mile=5.444
|road={{jct|state=MA|MA|2|dir1=west|name1=Concord Turnpike|city1=Concord}}
|notes=North end of concurrency with Route&nbsp;2
}}
{{MAint
|type=concur
|mile=5.820
|road={{jct|state=MA|MA|2A|MA|16|dir1=east|dir2=east|name1=[[Massachusetts Avenue (Boston)|Massachusetts Avenue]]|road|Alewife Brook Parkway|city1=Medford|location2=[[Harvard Square]]|city3=Cambridge}}
|notes=North end of concurrency with Route&nbsp;16; south end of concurrency with Route&nbsp;2A
}}
{{MAint
|type=concur
|location=Arlington
|lspan=3
|mile=7.198
|road={{jct|state=MA|MA|60|dir1=west|name1=Pleasant Street|city1=Belmont}}
|notes=South end of concurrency with Route&nbsp;60
}}
{{MAint
|type=concur
|mile=7.283
|road={{jct|state=MA|MA|60|name1=Chestnut Street|dir1=east|city1=Medford|city2=Malden}}
|notes=North end of concurrency with Route 60
}}
{{MAint
|type=concur
|mile=7.457
|road={{jct|state=MA|MA|2A|dir1=west|name1=Summer Street|road|Mystic Valley Parkway|city1=Lexington|city2=Concord}}
|notes=North end of concurrency with Route&nbsp;2A
}}
{{MAint|old
|location=Burlington
|lspan=4
|mile=13.442
|mspan=2
|place=Southern end of freeway section
}}
{{MAint|old
|mile=none
|old=33
|exit=51
|type=concur
|road={{jct|state=MA|I|95|dir1=north|name1=[[Massachusetts Route 128|Route 128]] north|MA|3A|dir2=north|city1=Burlington|city2=Peabody|location3=[[Portsmouth, New Hampshire|Portsmouth, NH]]}}
|notes=South end of [[Concurrency (road)#Wrong-way_concurrencies|wrong-way concurrency]] with I-95/Route&nbsp;128; signed as exits 51A (I-95) and 51B (Route 3A)
}}
{{MAint|old
|mile=14.874
|old=32B
|exit=50B
|road={{jct|state=MA|road|[[Middlesex Turnpike (Massachusetts)|Middlesex Turnpike]]|city1=Burlington}}
|notes=
}}
{{MAint|old
|mile=15.136
|type=concur
|old=32A (NB)<br>25B (SB)
|exit=50A (NB)<br>72B (SB)
|road={{jct|state=MA|I|95|dir1=south|MA|128|dir2=south|city1=Waltham|location2=[[Providence, Rhode Island|Providence, RI]]}}
|notes=North end of [[Concurrency (road)#Wrong-way_concurrencies|wrong-way concurrency]] with I-95/Route&nbsp;128; Route 128 not signed northbound
}}
{{MAint|old
|location=Bedford
|old=26
|exit=73
|mile=17.646
|road={{jct|state=MA|MA|62|city1=Burlington|city2=Bedford}}
}}
{{MAint|old
|location=Billerica
|lspan=2
|old=27
|exit=76
|mile=21.167
|road=Concord Road&nbsp;– [[Billerica, Massachusetts|Billerica]], [[Bedford, Massachusetts|Bedford]]
}}
{{MAint|old
|old=28
|exit=78
|mile=22.591
|road=Treble Cove Road&nbsp;– [[North Billerica, Massachusetts|North Billerica]], [[Carlisle, Massachusetts|Carlisle]]
}}
{{MAint|old
|location=Chelmsford
|lspan=6
|old=29
|exit=79
|mile=24.691
|road={{jct|state=MA|MA|129|city1=Billerica|city2=Chelmsford}}
}}
{{MAint|old
|old=30B
|exit=80
|mile=25.554
|type=incomplete
|road={{jct|state=MA|road|[[Lowell Connector]] north|to2=yes|I|495|dir2=north|city1=Lawrence}}
|notes=Northbound exit and southbound entrance; southern terminus and exit 1A on Lowell Connector
}}
{{MAint|old
|old=30
|exit=81
|mile=25.554
|mile2=26.108
|type=incomplete
|road={{jct|state=MA|I|495|road|[[Lowell Connector]] north|city1=Marlboro|city2=Lawrence}}
|notes=Signed as exits 81A (north) and 81B (south); no northbound access to I-495 north/Lowell; Lowell Connector not signed
}}
{{MAint|old
|old=31
|exit=81C
|mile=26.571
|road={{jct|state=MA|MA|110|city1=Chelmsford|city2=Lowell}}
}}
{{MAint|old
|old=32
|exit=84
|mile=28.762
|road={{jct|state=MA|MA|4|name1=North Road|city1=North Chelmsford|city2=Chelmsford}}
}}
{{MAint|old
|old=33
|exit=86
|mile=30.819
|road={{jct|state=MA|MA|40|city1=Westford|city2=North Chelmsford}}
}}
{{MAint|old
|location=Tyngsborough
|lspan=2
|old=34
|exit=88
|mile=33.029
|road=Westford Road&nbsp;– [[Tyngsborough, Massachusetts|Tyngsborough]], [[Westford, Massachusetts|Westford]]
}}
{{MAint|old
|old=35
|exit=90
|mile=34.644
|road={{jct|state=MA|MA|113|city1=Dunstable|city2=Tyngsborough}}
}}
{{jctint|old
|state_special=[[Massachusetts]]–<br />[[New Hampshire]] line
|sspan=2
|county_special=[[Middlesex County, Massachusetts|Middlesex]]–<br />[[Hillsborough County, New Hampshire|Hillsborough]] county line
|cspan=2
|location_special=[[Tyngsborough, Massachusetts|Tyngsborough]]–<br />[[Nashua, New Hampshire|Nashua]] line
|lspan=2
|type=incomplete
|mile=36.104
|mile2=0.000
|line=yes
|mspan=2
|old=36
|exit=91
|road=Middlesex Road – [[Tyngsborough, Massachusetts|Tyngsborough]]<br/>[[Daniel Webster Highway]] — [[South Nashua, New Hampshire|South Nashua NH]]
|notes=No southbound exit; northbound entrance extends into New Hampshire, where it merges with exit 1}}
{{jctplace|old
|type=trans
|mile=none
|place=Transition between Northwest Expressway and [[Everett Turnpike]]
}}
{{NHint|old
|sspan=82
|county=Hillsborough
|cspan=18
|location=Nashua
|lspan=9
|mile=0.834
|exit=1
|road=Spit Brook Road&nbsp;– [[South Nashua, New Hampshire|South Nashua]]
|notes=}}
{{NHint|old
|mile=1.553
|exit=2
|road={{jct|state=NH|NH|3A|to1=yes|road|[[Daniel Webster Highway]]|city1=Hudson}}
|notes=Access via [[Circumferential Highway (Nashua)|Circumferential Highway]]; signed as exit 1A from northbound collector-distributor lane}}
{{NHint|old
|mile=2.819
|exit=3
|type=incomplete
|road=[[Daniel Webster Highway]]&nbsp;– [[South Nashua, New Hampshire|South Nashua]]
|notes=Southbound left exit and northbound entrance}}
{{NHint|old
|mile=3.055
|exit=4
|road=East Dunstable Road
|notes=[[Boston Air Route Traffic Control Center|FAA Center]] signage was removed at the request of the [[Federal Aviation Administration|FAA]] shortly after [[September 11, 2001 attacks|9/11]]}}
{{NHint|old
|mile=4.724
|exit=5
|road={{jct|state=NH|NH|111|NH|111A|dir2=west|city1=Nashua|city2=Hudson|areadab2=CDP|location3=[[Pepperell, Massachusetts|Pepperell, MA]]}}
|notes=Signed as exits 5E (east) and 5W (west)}}
{{NHint|old
|mile=5.059
|type=incomplete
|exit=5A
|road=Simon Street
|notes=Northbound exit only}}
{{NHint|old
|mile=6.285
|exit=6
|road={{jct|state=NH|NH|130|name1=Broad Street|city1=Nashua|city2=Hollis|city3=Brookline}}
|notes=}}
{{NHint|old
|exit=7
|mile=6.781
|mspan=2
|type=concur
|road={{jct|state=NH|NH|101A|Turnpike|Everett|dir2=north|city1=Manchester|city2=Concord|location3=[[Nashua, New Hampshire|Nashua Downtown]]|city4=Amherst|city5=Milford|areadab5=CDP}}
|notes=Signed as exits 7E (east) and 7W (north/west); northern end of concurrency with Everett Turnpike}}
{{NHint|old
|mile=none
|place=Northern end of freeway section}}
{{NHint|old
|espan=15
|ospan=15
|location=Merrimack
|lspan=3
|mile=10.832
|road={{jct|state=NH|Turnpike|Everett|to1=yes}}
|notes=Access via Industrial Drive}}
{{NHint
|mile=12.109
|road={{jct|state=NH|Turnpike|Everett|city1=Concord|location2=[[Boston]]}}
|notes=Exit 11 on Everett Turnpike; access via Greeley Street}}
{{NHint
|mile=15.745
|road={{jct|state=NH|Turnpike|Everett|dir1=south}}
|notes=Exit 12 on Everett Turnpike; access via Bedford Road}}
{{NHint
|location=Bedford
|lspan=3
|mile=17.874
|mile2=18.148
|road={{jct|state=NH|Turnpike|Everett|to2=y|NH|3A|location1=[[Manchester–Boston Regional Airport|Manchester Airport]]|city2=Litchfield|city3=Concord|city4=Nashua|extra=airport}}
|notes=Exit 13 on Everett Turnpike; access via [[Raymond Wieczorek Drive]]}}
{{NHint
|mile=20.900
|road={{jct|state=NH|dir3=east|I|293|Turnpike|Everett|NH|101|extra=airport|location1=[[Boston]]|city2=Concord|city3=Manchester Airport}}
}}
{{NHint
|mile=21.331
|road={{jct|state=NH|to1=yes|NH|101|NH|114|dir1=west|location1=[[Bedford, New Hampshire|Bedford Ctr.]]|city2=Milford}}
|notes=Access via Kilton Road}}
{{NHint
|location=Manchester
|lspan=3
|mile=22.690
|type=concur
|road={{jct|state=NH|I|293|name1=[[Everett Turnpike]]|NH|3A|dir2=north|NH|114A|dir3=west|city1=Concord|location2=[[Boston]]}}
|notes=Exit 4 on I-293; eastern terminus of NH&nbsp;114A; southern terminus of [[wrong-way concurrency]] with NH&nbsp;3A}}
{{NHint
|mile=23.333
|type=concur
|road={{jct|state=NH|NH|3A|dir1=south|name1=South Elm Street}}
|notes=Northern end of wrong-way concurrency with NH&nbsp;3A}}
{{NHint
|mile=25.974
|type=concur
|road={{jct|state=NH|NH|28|dir1=south|name1=Beech Street&nbsp;/ Maple Street}}
|notes=Southern end of concurrency with NH&nbsp;28}}
{{NHint
|county=Merrimack
|cspan=17
|location=Hooksett
|lspan=4
|mile=26.998
|mile2=27.591
|road={{jct|state=NH|I|93|NH|101|to2=yes|city1=Salem|location2=[[Boston]]|city3=Concord|city4=Plymouth}}
|notes=Exit&nbsp;9 on I-93}}
{{NHint
|mile=28.586
|road={{jct|state=NH|NH|28A|dir1=south|name1=[[Mammoth Road]]|city1=Londonderry}}
|notes=Northern terminus of NH&nbsp;28A}}
{{NHint
|mile=29.082
|road={{jct|state=NH|NH|27|dir1=east|city1=Candia|city2=Raymond|areadab2=CDP}}
|notes=Western terminus of NH&nbsp;27}}
{{NHint
|mile=29.578
|road={{jct|state=NH|NH|28 Bypass|dir1=south|city1=Derry|areadab1=CDP}}
|notes=Northern terminus of NH&nbsp;28 Bypass}}
{{NHint
|location=Allenstown
|mile=35.237
|type=concur
|road={{jct|state=NH|NH|28|dir1=north|city1=Epsom|city2=Alton}}
|notes=Northern end of concurrency with NH&nbsp;28}}
{{NHint
|location=Pembroke
|mile=39.506
|road={{jct|state=NH|NH|106|dir1=north|city1=Loudon|areadab1=CDP|city2=Laconia}}
|notes=Southern terminus of NH&nbsp;106}}
{{jctbridge|old
|state=NH
|location=Concord
|lspan=6
|mile=41.704
|bridge=Korean Veterans Memorial Bridge over the [[Merrimack River]]
}}
{{NHint|old
|espan=37
|ospan=37
|mile=41.775
|mile2=41.933
|road={{jct|state=NH|I|93|name1=[[Everett Turnpike]]|I|89|I|393|dir2=north|dir3=east|to2=yes|city1=Manchester|city2=Lebanon|city3=Plymouth|city4=Portsmouth}}
|notes=Exit 13 on I-93}}
{{NHint
|mile=42.173
|road={{jct|state=NH|NH|3A|dir1=south|name1=Main Street}}
|notes=Southern end of silent concurrency with NH&nbsp;3A}}
{{NHint
|mile=42.729
|type=concur
|road={{jct|state=NH|US|202|NH|9|dir1=west|dir2=west|name2=Pleasant Street}}
|notes=Southern end of concurrency with US&nbsp;202&nbsp;/ NH&nbsp;9}}
{{NHint
|mile=43.024
|type=concur
|road={{jct|state=NH|NH|9|I|93|dir1=east|to2=yes|name1=Loudon Road}}
|notes=Northern end of concurrency with NH&nbsp;9}}
{{NHint
|mile=43.411
|type=concur
|road={{jct|state=NH|US|202|dir1=east|to2=yes|I|393|dir2=east}}
|notes=Northern end of concurrency with US&nbsp;202}}
{{NHint
|location=Boscawen
|lspan=2
|mile=50.812
|type=concur
|road={{jct|state=NH|US|4|I|93|dir1=east|to2=y|city1=Concord}}
|notes=Southern end of concurrency with US&nbsp;4}}
{{NHint
|mile=52.168
|type=concur
|road={{jct|state=NH|US|4|dir1=west|city1=Salisbury|city2=Andover}}
|notes=Northern end of concurrency with US&nbsp;4}}
{{NHint
|location=Franklin
|lspan=3
|mile=60.645
|type=concur
|road={{jct|state=NH|NH|127|dir1=south|city1=Salisbury}}
|notes=Southern end of concurrency with NH&nbsp;127}}
{{NHint
|mile=61.307
|type=concur
|road={{jct|state=NH|NH|3A|NH|11|dir1=north|dir2=west|city1=Andover|city2=Bristol|areadab2=CDP}}
|notes=Northern end of concurrency with NH&nbsp;3A; southern end of concurrency with NH&nbsp;11}}
{{NHint
|mile=61.755
|type=concur
|road={{jct|state=NH|NH|127|dir1=north|city1=New Hampton|areadab1=CDP}}
|notes=Northern end of concurrency with NH&nbsp;127}}
{{NHint
|county=Belknap
|cspan=14
|location=Tilton
|lspan=3
|mile=64.925
|type=concur
|road={{jct|state=NH|NH|132|I|93|dir1=south|dir2=south|to2=yes|city1=Northfield|city2=Concord}}
|notes=Southern end of concurrency with NH&nbsp;132}}
{{NHint
|mile=66.203
|mile2=66.586
|road={{jct|state=NH|I|93|city1=Canterbury|city2=Concord|location3=[[Boston]]|city4=New Hampton|city5=Plymouth|NH|140|dir2=east|city6=Belmont|city7=Gilmanton}}
|notes=Exit&nbsp;20 on I-93; western terminus of NH&nbsp;140}}
{{NHint
|mile=66.678
|type=concur
|road={{jct|state=NH|NH|132|dir1=north|city1=Sanbornton}}
|notes=Northern end of concurrency with NH&nbsp;132}}
{{NHint
|location=Belmont
|mile=72.845
|road={{jct|state=NH|US-Bus|3|NH|11A|dir1=north|dir2=east|location2=[[Laconia, New Hampshire|Laconia]] downtown}}
|notes=Southern terminus of US 3 Business, western terminus of NH&nbsp;11A}}
{{NHint
|location=Laconia
|lspan=2
|mile=74.355
|type=incomplete
|road={{jct|state=NH|NH|106|to2=to|NH|107|city1=Laconia|city2=Belmont|areadab2=CDP|city3=Concord}}
|notes=Interchange; no southbound access to NH&nbsp;106 north}}
{{NHint
|mile=74.999
|type=incomplete
|road={{jct|state=NH|NH|107|city1=Laconia|city2=Gilmanton}}
|notes=Interchange; southbound exit and northbound entrance}}
{{NHint
|location=Gilford
|lspan=2
|mile=76.040
|road={{jct|state=NH|NH|11A|city1=Gilford|city2=Laconia}}
|notes=Interchange}}
{{NHint
|mile=78.649
|type=concur
|road={{jct|state=NH|NH|11|dir1=east|city1=Alton|areadab1=CDP}}
|notes=Northern end of concurrency with NH&nbsp;11}}
{{NHint
|location1=Gilford
|location2=Laconia
|mile=79.442
|road={{jct|state=NH|US-Bus|3|NH|107|dir1=south|dir2=south|name1=Union Avenue|city1=Laconia}}
|notes=Northern terminus of US 3 Business and NH&nbsp;107}}
{{NHint
|location=Laconia
|mile=82.684
|road={{jct|state=NH|NH|11B|dir1=south|city1=Gilford|city2=Alton Bay}}
|notes=Northern terminus of NH&nbsp;11B}}
{{NHint
|location=Meredith
|lspan=3
|mile=86.334
|road={{jct|state=NH|NH|106|dir1=south|city1=Laconia}}
|notes=Northern terminus of NH&nbsp;106}}
{{NHint
|mile=86.847
|road={{jct|state=NH|NH|104|I|93|dir1=west|to2=y|city1=New Hampton|areadab1=CDP}}
|notes=Eastern terminus of NH&nbsp;104}}
{{NHint
|mile=87.693
|type=concur
|road={{jct|state=NH|NH|25|dir1=east|city1=Center Harbor|city2=Ossipee|city3=Conway}}
|notes=Southern end of concurrency with NH&nbsp;25}}
{{NHint
|location=Center Harbor
|mile=90.778
|road={{jct|state=NH|NH|25B|dir1=east|city1=Center Harbor}}
|notes=Western terminus of NH&nbsp;25B}}
{{NHint
|county=Grafton
|cspan=18
|location=Holderness
|lspan=2
|mile=95.526
|road={{jct|state=NH|NH|113|dir1=east|city1=Sandwich}}
|notes=Western terminus of NH&nbsp;113}}
{{NHint
|mile=96.661
|road={{jct|state=NH|NH|175|dir1=north|city1=Campton}}
|notes=Southern terminus of NH&nbsp;175}}
{{NHint
|location=Ashland
|lspan=2
|mile=99.271
|road={{jct|state=NH|NH|132|dir1=south|city1=New Hampton|areadab1=CDP|city2=Tilton}}
|notes=Northern terminus of NH&nbsp;132}}
{{NHint
|mile=99.958
|mile2=100.339
|road={{jct|state=NH|I|93|city1=Tilton|city2=Concord|city3=Plymouth|city4=Campton}}
|notes=Exit 24 on I-93}}
{{NHint
|location=Plymouth
|lspan=2
|mile=105.397
|road={{jct|state=NH|NH|175A|I|93|dir1=east|to2=yes|city1=Holderness}}
|notes=Western terminus of NH&nbsp;175A}}
{{NHint
|mile=106.202
|type=concur
|road={{jct|state=NH|NH|3A|NH|25|dir1=south|dir2=west|to3=to|I|93|city1=Rumney|city2=Bristol|areadab2=CDP|city3=Concord|city4=Littleton}}
|notes=Interchange; northern end of concurrency with NH&nbsp;25; northern terminus of NH&nbsp;3A}}
{{NHint
|location=Campton
|lspan=2
|mile=109.525
|road={{jct|state=NH|I|93|city1=Campton|city2=Littleton|city3=Plymouth|city4=Concord}}
|notes=Access via Blair Road; exit 27 on I-93}}
{{NHint
|mile=112.375
|road={{jct|state=NH|NH|49|I|93|dir1=east|to2=yes|city1=Campton|city2=Waterville Valley}}
|notes=Western terminus of NH&nbsp;49}}
{{NHint
|location=Thornton
|mile=113.804
|mile2=114.101
|road={{jct|state=NH|I|93|city1=Plymouth|city2=Concord|city3=Franconia|city4=Littleton}}
|notes=Exit 29 on I-93}}
{{NHint
|location=Woodstock
|lspan=3
|mile=120.410
|mile2=120.910
|road={{jct|state=NH|I|93|city1=Franconia|city2=Littleton|location3=[[St. Johnsbury, VT]]|city4=Plymouth|city5=Concord}}
|notes=Exit 30 on I-93}}
{{NHint
|mile=125.420
|road={{jct|state=NH|NH|175|dir1=south|city1=Campton}}
|notes=Northern terminus of NH&nbsp;175}}
{{NHint
|mile=126.031
|road={{jct|state=NH|NH|112|I|93|to2=yes|city1=Lincoln|areadab1=CDP|city2=Conway|areadab2=CDP|city3=Woodsville}}
|notes=}}
{{NHint
|location=Lincoln
|lspan=2
|mile=128.210
|mile2=128.394
|road={{jct|state=NH|I|93|city1=Concord|city2=Littleton}}
|notes=Exit 33 on I-93}}
{{NHint|old
|exit=34A
|mile=131.562
|type=concur
|road={{jct|state=NH|I|93|dir1=south}}
|notes=Southbound exit only; southern end of concurrency with I-93}}
{{NHint|old
|location=Franconia
|lspan=4
|mile=135.923
|exit=34B
|road=[[Cannon Mountain (New Hampshire)|Cannon Mountain]] Tramway&nbsp;– [[Old Man of the Mountain|Old Man Historic Site]]
|notes=}}
{{NHint|old
|mile=136.623
|exit=34C
|road={{jct|state=NH|NH|18|dir1=north|location1=[[Echo Lake (Franconia Notch)|Echo Lake]] Beach|location2=Peabody Slopes|location3=[[Cannon Mountain Ski Area|Cannon Mountain]]|location4=[[Franconia, New Hampshire|South Franconia]]}}
|notes=Southern terminus of NH&nbsp;18}}
{{NHint|old
|exit=35
|mile=138.080
|type=concur
|road={{jct|state=NH|I|93|dir1=north}}
|notes=Northbound exit only; northern end of concurrency with I-93}}
{{NHint|old
|espan=16
|ospan=16
|mile=139.044
|road={{jct|state=NH|NH|141|dir1=west|to2=yes|I|93|dir2=north|city1=Franconia}}
|notes=Eastern terminus of NH&nbsp;141
}}
{{NHint
|county=Coos
|cspan=15
|location=Carroll
|lspan=2
|mile=148.497
|road={{jct|state=NH|US|302|city1=Bethlehem|areadab1=CDP|city2=Bretton Woods|city3=Conway}}
|notes=Village of [[Twin Mountain, New Hampshire|Twin Mountain]]}}
{{NHint
|mile=150.510
|road={{jct|state=NH|NH|115|dir1=north|city1=Jefferson|city2=Berlin|city3=Gorham|areadab3=CDP}}
|notes=Southern terminus of NH&nbsp;115}}
{{NHint
|location=Whitefield
|lspan=3
|mile=156.871
|type=concur
|road={{jct|state=NH|NH|116|NH|142|dir1=south|dir2=south|city1=Bethlehem|areadab1=CDP|city2=Littleton|areadab2=CDP}}
|notes=Southern end of concurrency with NH&nbsp;116&nbsp;/ NH&nbsp;142}}
{{NHint
|mile=156.918
|type=concur
|road={{jct|state=NH|NH|142|dir1=north|city1=Dalton}}
|notes=Northern end of concurrency with NH&nbsp;142}}
{{NHint
|mile=156.959
|type=concur
|road={{jct|state=NH|NH|116|dir1=north|city1=Jefferson|city2=Gorham}}
|notes=Northern end of concurrency with NH&nbsp;116}}
{{NHint
|location=Lancaster
|lspan=3
|mile=165.330
|type=concur
|road={{jct|state=NH|US|2|dir1=east|city1=Jefferson|city2=Gorham|areadab2=CDP|city3=Berlin}}
|notes=Southern end of concurrency with US&nbsp;2}}
{{NHint
|mile=165.372
|road={{jct|state=NH|NH|135|dir1=south|city1=Dalton|location2=[[Lunenburg, Vermont|Gilman VT]]}}
|notes=Northern terminus of NH&nbsp;135}}
{{NHint
|mile=166.126
|type=concur
|road={{jct|state=NH|US|2|dir1=west|location1=[[Vermont]]}}
|notes=Northern end of concurrency with US&nbsp;2
}}
{{NHint
|location=Northumberland
|mile=175.152
|road={{jct|state=NH|NH|110|dir1=east|city1=Stark|city2=Berlin}}
|notes=Western terminus of NH&nbsp;110; village of [[Groveton, New Hampshire|Groveton]]}}
{{NHint
|location=North Stratford
|mile=188.576
|road={{jct|state=NH|VT|105|to1=to|dir1=west|location1=[[Bloomfield, Vermont|Bloomfield VT]]}}
|notes=Access via Bridge Street}}
{{NHint
|location=Colebrook
|lspan=3
|mile=201.458
|type=concur
|road={{jct|state=NH|NH|26|dir1=east|city1=Dixville Notch}}
|notes=Southern end of concurrency with NH&nbsp;26}}
{{NHint
|mile=201.565
|type=concur
|road={{jct|state=NH|NH|26|dir1=west|name1=Bridge Street}}
|notes=Northern end of concurrency with NH&nbsp;26
}}
{{NHint
|mile=201.647
|road={{jct|state=NH|NH|145|dir1=north|city1=Clarksville}}
|notes=Southern terminus of NH&nbsp;145}}
{{NHint
|location=Pittsburg
|lspan=2
|mile=219.573
|road={{jct|state=NH|NH|145|dir1=south|city1=Colebrook}}
|notes=Northern terminus of NH&nbsp;145}}
{{NHint
|mile=241.953
|road={{jct|province=QC|QC|257|dir1=north}}
|notes=Continuation into [[Quebec]]}}
{{Jctbtm|col=9|keys=incomplete,concur,trans}}

==Special routes==
US&nbsp;3 has one existing [[special route]], a [[business route]] through [[Laconia, New Hampshire]]. Four other special routes may have existed in the past: an alternate and business route between [[Tyngsborough, Massachusetts]], and [[Concord, New Hampshire]], and bypass routes around Concord and [[Nashua, New Hampshire]].

===Tyngsborough–Concord alternate route===
{{empty section|date=February 2023}}
{{Infobox road small
|state=NH
|type=US-Alt
|route=3
|location=[[Tyngsborough, Massachusetts]]–[[Concord, New Hampshire]]
|header_type=former
}}
{{-}}

===Tyngsborough–Concord business route===
{{empty section|date=February 2023}}
{{Infobox road small
|state=NH
|type=US-Bus
|route=3
|location=[[Tyngsborough, Massachusetts]]–[[Concord, New Hampshire]]
|header_type=former
}}
{{-}}

===Concord bypass route===
{{empty section|date=February 2023}}
{{Infobox road small
|state=NH
|type=US-Byp
|route=3
|location=[[Concord, New Hampshire]]
|header_type=former
}}
{{-}}

===Nashua bypass route===
{{empty section|date=February 2023}}
{{Infobox road small
|state=NH
|type=US-Byp
|route=3
|location=[[Nashua, New Hampshire]]
|header_type=former
}}
{{-}}

===Laconia business loop===
{{Infobox road small
|state=NH
|type=US-Bus
|route=3
|location=[[Belmont, New Hampshire|Belmont]]–[[Laconia, New Hampshire|Laconia]], New Hampshire
|length_mi=4.144
|length_ref=<ref name="NHDOT Roads"/>
}}
[[File:US Route 3 North Business loop sign in Laconia.jpg | thumb|220x124px | right | alt= US Route 3 sign with Business sign above and direction sign below | US&nbsp;3 Bus. sign]]
'''U.S. Route&nbsp;3 Business''' ('''US&nbsp;3 Bus.''') is a {{convert|4.144|mi|km|adj=mid|-long}}<ref name="NHDOT Roads" /> signed [[business route]] running north–south through downtown [[Laconia, New Hampshire]]. It runs from US&nbsp;3 and [[New Hampshire Route 11|NH&nbsp;11]] in [[Belmont, New Hampshire|Belmont]] north to US&nbsp;3 in Laconia, along [[New Hampshire Route 107|NH&nbsp;107]] and [[New Hampshire Route 11A|NH&nbsp;11A]]. It is a former alignment of US&nbsp;3, used before the Laconia–Gilford bypass was built.
{{-}}

==See also==
* {{Portal-inline|United States}}
* {{Portal-inline|U.S. Roads}}

==References==
{{reflist}}

==External links==
{{Attached KML}}
{{Commons category|U.S. Route 3}}
* [http://www.bostonroads.com/roads/northwest/ US 3/Northwest Expressway on Bostonroads.com]
* [https://web.archive.org/web/20120707163744/http://granitehighways.com/?roadwayname=U.S.+Route+3+%2F+Daniel+Webster+Highway Photos of US 3 in New Hampshire]
* [http://usends.com/3.html Endpoints of U.S. Highway 3]

{{US Highways}}

{{start srbox}}
{{ma browse|previous_type=Route|previous_route=2A|route=[[List of numbered routes in Massachusetts|MA]]|next_type=Route|next_route=3}}
{{nh browse|previous_type=US|previous_route=2|route=[[New Hampshire Highway System|NH]]|next_type=NH|next_route=3A}}
{{New England browse|previous_route=5|next_route=6A}}
{{s-end}}

{{DEFAULTSORT:U.S. Route 03}}
[[Category:U.S. Route 3| ]]
[[Category:United States Numbered Highway System|03]]
[[Category:U.S. Highways in New Hampshire|03]]
[[Category:U.S. Highways in Massachusetts|03]]
[[Category:Transportation in Middlesex County, Massachusetts]]
[[Category:Transportation in Hillsborough County, New Hampshire]]
[[Category:Transportation in Merrimack County, New Hampshire]]
[[Category:Transportation in Belknap County, New Hampshire]]
[[Category:Transportation in Grafton County, New Hampshire]]
[[Category:Transportation in Coös County, New Hampshire]]